Preparation method of semiconductor structure

Abstract

The invention relates to a preparation method of a semiconductor structure. The method comprises the steps of providing a target material layer; forming a first mask layer and a second mask layer on the upper surface of the target material layer, wherein the first mask layer and the second mask layer are sequentially stacked on the target material layer; etching the second mask layer based on the first mask layer to form a second opening pattern, wherein the side wall of the second opening pattern is an inclined side wall; and etching the target material layer based on the second mask layer and the second opening pattern. In the process of etching the target material layer based on the second mask layer, the inclined side wall of the second opening pattern gradually retreats, so that the target material layer below the second mask layer is gradually exposed and etched, the etching degrees of all parts of the target material layer are inconsistent, and under the inconsistency, the morphology of the target material layer formed by etching is at a certain inclination angle.

Description

technical field [0001] The invention relates to the field of semiconductors, in particular to a method for preparing a semiconductor structure. Background technique [0002] With the improvement of the performance of semiconductor devices, it is necessary to etch to form different shapes in the manufacturing process of semiconductor devices. For example, for the formation of a gentle slope microstructure, the existing technology is to increase the content of polymer during the etching process. Therefore, a large amount of polymer gas is used to protect the sidewall, so that the sidewall gradually slopes during etching, and finally forms a gentle slope microstructure. [0003] However, the inclined angle of the dielectric layer formed by this method is limited, and too much polymer will cause the problem of etching stop during the etching process. Similarly, too much polymer gas will affect the atmosphere in the etching chamber. Increase the cycle of machine PM, thus increas...

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Problems solved by technology

[0003] However, the inclined angle of the dielectric layer formed by this method is limited, and too much polymer will cause the problem of etching stop during the etching process. Similarly, too much polymer gas will affect the atmosphere in the etching chamber. Increase the cycle of machine PM, thus greatly increasing the investment of industrial costs

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